Just as European marine paint companies have been putting the issue of the tributyltin (TBT) pollutant behind them, they are now facing new difficulties with biocides in anti-fouling coatings.

Environmental NGOs, like the World Wildlife Fund (WWF), are claiming that ship owners, mainly of small vessels, are still breaching regulations in Europe banning TBT on boats. But it is exonerating the paint companies or the shipping lines for any blame, after both the EU coatings sector and shipping industry have abandoned the production or use of TBT coatings.

The use of TBT is one area of environmental concern where the coatings industry and its customers in the developed world-in particular Europe, North America and Japan-are acting well ahead of the legislators.

The vast majority of coatings companies in the industrial world no longer make TBT paints, while most major shipping lines are complying with a voluntary ban on it. Both the coatings producers and shipping companies are already looking beyond TBT alternatives to the application of anti-fouling paints which not only do no harm to marine life but actually help the environment by saving fuel.

"TBT is virtually a matter of history as far as the major coatings companies are concerned because we haven't been making TBT paints since 2003," said an official at the European trade association for coatings and inks (Cepe). "With regard to EU regulations of marine paints, our major concern at the moment is the assessment and authorization of anti-fouling paints under recent EU legislation on biocides."

"Companies making anti-fouling paints are having to gather a lot of data together for the creation of dossiers on their products, on the basis of these authorizations will be given," the official added.

The EU's biocides products directive, which has been incorporated into the statute books of the 25 member states, was approved in 1998. But the EU authorities have only recently started the process of drawing up positive lists of permitted active substances. The next stage is the authorization of products containing biocides, such as anti-fouling coatings.

"Dossiers on anti-fouling paints will not have to start to be submitted until 2008 but there are a lot of technical guidance issues to be sorted out as soon as possible," said the Cepe official. "We do not know yet, for example, exactly what types of tests will be required. We are working on simulated models which give some idea of what happens to compounds in the aquatic environment."

"It is also still not clear whether the approval of a dossier in one of the EU member states will be sufficient to gain approval in the others," he explained. "It is a question of whether a system of mutual recognition would operate in such a way that one approval would be adequate."

The NGOs, which have been exerting a lot of influence in gaining bans on TBT, have indicated that they will be keeping a close eye on the approval of biocides in anti-fouling coatings as well as other products. This will particularly apply to biocides, which are categorized as being persistent, bioaccumulative and toxic (PBT).

However the more immediate priority for organizations like WWF is to make more effective the current global ban on TBT paints which has been introduced by the UN International Maritime Organization (IMO).

WWF, one of the largest of the international environmental groups, has been complaining about continued pollution from TBT. It has just submitted a paper to the IMO showing that TBT is still causing harm to marine life on a global scale.

"There is evidence that there are a lot of stocks of TBT paints still around in Europe," said Simon Walmsley, head of WWF-UK's marine program. "We also know that it is being used on small vessels-like yachts and pleasure craft-even though the application of TBT paints on these sorts of ships has been banned in the EU since 1987. Outside the EU, the situation is much worse, especially in the Far East, where TBT is being painted on much larger vessels."

A recent WWF study of chemicals in foods found that TBT and its derivatives are still contaminating food products from around Europe. In the environment the group points to data showing traces of TBT appearing in mussels, oysters, clams and other shell life as well as high contamination of a range of other marine animals such as skipjack tuna and harbour porpoises

WWF said the continued TBT pollution is a scandal, which the world should be ashamed of. "Forty years after TBT's negative impacts were first identified and five years after the legislation to ban it was agreed (in the IMO), TBT is still being used, indiscriminately polluting global marine life and our food chain," said Walmsley.

The NGO has few, if any, complaints about the coatings sector or shipping industries. Instead its anger is directed at the vast majority of the IMO's 166 member countries who have not ratified the TBT agreement. "Generally the shipping and paint industries support the legislation being ratified," added Walmsley. "Delegates at the IMO whose countries have not signed up should be ashamed."

"TBT is one of the most lethal chemical pollutants," he continues. "But we are worried about other biocides. Some are better than others. But overall we would like them not to be used at all in anti-fouling paints because by definition they are toxic, while they can also be persistent and bioaccumulative in the environment."

Coatings companies stress that their ambition now is to develop paints that keep organisms off the hulls of vessels without the use of biocide coatings. There are, for example, silicon-based anti-fouling coatings –or fouling release coatings (FRCs)-which not only combat organisms without the use of biocides but also reduce the energy consumption of large vessels.